While I was fortunate glass didn't get into the pool, a few years ago we had a big storm that smashed my glass top patio table into a zillion pieces that was sitting on a nearby brick patio. I spent over 4 hours vacuuming and revacuuming the brick patio with a shop vac to get rid of the glass. I swore after that I would never own a glass top patio table again (the new table has nice heavy tiles).

I wish I had an easy solution for you, but I was also thinking a battery powered device like Ben mentioned may work.

Let us know what you do and how it goes.